We propose to establish a center with laboratory, clinical, research, and education components in order to improve our ability to diagnose, treat, and prevent HIV infection. We propose to develop a set of core laboratories and facilities to 1) provide special assays of importance for measuring immunological, virological, and serological aspects of HIV infection, 2) develop a pharmacokinetics laboratory to follow levels of anti-HIV therapeutic agents, and 3) establish the necessary computer and biostatistics facilities for evaluation of the data. The clinical studies are intended to 1) analyze the diversity and significance of neuropsychiatric abnormalities at all stages of HIV infection, 2) evaluate anti-HIV therapeutic agents in a broad group of symptomatic infected patients, and 3) develop improved treatment approaches to AIDS-associated opportunistic infections such as cryptococcal meningitis and disseminated cytomegalovirus infection. The specific goals for the basic research studies are to 1) develop and apply improved measures of virus load in clinical samples, 2) examine quantitative and qualitative abnormalities of T and B-lymphocytes and monocytes at all stages of HIV infection, 3) use murine models of cryptococcal infection for the development of new therapeutic approaches, and 4) study the epidemiology of HIV and related viruses including HTLV-L, HTLV- II, and HTLV-IV in a high risk population in our community. We plan to expand and evaluate our presently developed educational programs which have been directed to gay and drug-abusing individuals, as well as other individuals, including school teacher, high school and college students, and physicians, nurses, other medical personnel, as well as the general population in smaller communities within several hundred miles of the St. Louis area. The latter activities are especially important in prevention of spread of this virus in our community, which has a relatively low overall prevalence of infection.